Take note, former currency depressed (4,4)

I believe the answer is:

mark down

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'take note' is the definition.
'mark down' can be an answer for 'note' (thesaurus). I'm not sure about the 'take' bit.

'former currency depressed' is the wordplay.
'former currency' becomes 'mark' (I have seen 'old currency' mean 'mark' so perhaps 'currency' could also mean 'mark'. I am not sure about the 'former' bit.).
'depressed' becomes 'down' (synonyms).
'mark'+'down'='MARK-DOWN'

Can you help me to learn more?

(Other definitions for mark down that I've seen before include "Lower cost" , "Score points off" , "Reduce in price" .)

I've seen this clue in The Telegraph.

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